Abstract: The invention provides a bandmill having an endless loop of bandsaw blade which is automatically strained to a desired tension, and automatically driven at an accurate location or tracking position. The bandmill runs on a pair of spaced co-planar wheels, which are forced longitudinally apart to apply strain to the bandsaw. Actual saw strain is automatically detected by a force transducer within the strain mechanism, and the actual saw strain is automatically compared electronically with a desired saw strain. A servo-controller automatically adjusts distance between the wheels to vary force therebetween so that actual saw strain is varied to approach the desired saw strain. Also, actual tracking of the saw blade relative to the wheels is automatically sensed by sensors located adjacent the edge of the saw blade.

Abstract: A bandmill has first and second wheels and an endless saw blade trained about the wheels. The wheels are mounted to rotate about respective axes which lie in a common plane, but the first wheel is adjustable in position relative to the second wheel with respect to both its distance from the second wheel and its orientation relative to the second wheel. A tensioning mechanism is effective to force the first wheel away from the second wheel, while maintaining the axes of rotation of the two wheels substantially parallel, in response to a signal which is provided by a load cell and represents the tension in the saw blade. A wheel tilt mechanism is effective to adjust the angular position of the first wheel relative to the second wheel in response to a signal indicating the path followed by the saw blade, for maintaining the blade on a proper path.

Abstract: An end-dogging log carriage including a first dog assembly with a first dog member rotatably mounted thereon and a second dog assembly with a second dog member rotatably mounted thereon. A log is supported solely by the first and second dog members engaging opposite ends of the log. At least one of the dog members is movable horizontally and vertically to orient the log to a desired position for sawing the log. There may be an indexing device operatively connected to one of the dog members through a clutch. The log may be rotated for scanning when the clutch is disengaged. The indexing device and the clutch are engaged after the log is oriented in a rotational position for a first sawing operation. The clutch is left engaged and the indexing device is employed to rotate the log through the required angle for the next sawing operation.

Abstract: In an automatic sawmill, logs are first sawn horizontally into pieces that are respectively deposited flat side down on a bed plate and conveyed through multiple, close spaced horizontal bandsaws located above the bed plate. Sawn cants are positioned by clamps to have their waney edges removed by a flying saw after clamp retraction.

Abstract: Intermediate dogging device to limit lateral deflection of a log held in end dogging log carriage. When a log is machined, residual stresses within the wood, weight of the wood, and sawing forces tend to deflect unsupported portions of the log, reducing cut accuracy. An intermediate dog is mounted on carriage between end dogs generally adjacent central plane containing feed axis. The intermediate dog extends from carriage and engages the log extending between the end dogs to reduce movement of log relative to carriage.